keepalive.mm

/**
--------------------------------------------------------------------------------
-   Module      :   keepalive.mm
-   Description :   A wrapper to keep an app alive, written
-                   in C++ and Objective-C so made for the OSX platform.
-   Author      :   Tim Zaman, 18-FEB-2016
--------------------------------------------------------------------------------
*/

#include "keepalive.h"
#import <IOKit/pwr_mgt/IOPMLib.h>

// kIOPMAssertionTypeNoDisplaySleep prevents display sleep,
// kIOPMAssertionTypeNoIdleSleep prevents idle sleep

//reasonForActivity is a descriptive string used by the system whenever it needs 
//  to tell the user why the system is not sleeping. For example, 
//  "Mail Compacting Mailboxes" would be a useful string.

IOPMAssertionID assertionID;

void KeepAlive::KeepAliveMM(){
    // NOTE: IOPMAssertionCreateWithName limits the string to 128 characters. 
    CFStringRef reasonForActivity = CFSTR("Program Running.");
    IOReturn success = IOPMAssertionCreateWithName(kIOPMAssertionTypeNoDisplaySleep, 
                                kIOPMAssertionLevelOn, reasonForActivity, &assertionID); 
    if (success == kIOReturnSuccess){
        // @TODO?
    } else {
        // @TODO?
    }
}

void KeepAlive::KeepAliveDestructorMM(){
    IOReturn success = IOPMAssertionRelease(assertionID);
}